The invention relates to a device for detecting a filling level, particularly of a liquid, in a container, by use of an electro-mechanical transducer mounted on a diaphragm. The transducer induces vibrations in the diaphragm in response to energization of the transducer by electrical means. The device includes a holder of the diaphragm on which the diaphragm is secured by means of a cylindrical intermediate member. Since vibrations imparted to the liquid by oscillations of the diaphragm have characteristics dependent on the quantity of liquid in the container, which characteristics are employed by electrical circuitry for measurement of the quantity of liquid.
Such known devices may not have very high resistance against various external influences which act on them. These influences may impair the operation of the device. Such influences result in, for example, distortions of the diaphragm, which may be brought about by temperature fluctuations or by deformation of the fastening of the cylindrical intermediate member to the diaphragm, or the holder. Furthermore, acoustic impairments of the diaphragm can occur, which can impair the measurement.